Dynamo-electric machine.



l. B. WIABD.

AM CTRIC MACHINE.

CAT 115D 111111115. 1914.

Fig.

IWIT-"115"SSE'S IN VENTUB.

UNITED STATES PATENT EEEQE,

JOHN B. WIARD, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL EIiECTRICCOMPANY, A CORPORATION OF NEW YORK.

DYNAMG-ELECTRC MACHINE.

Application led May 15, 1914.

tact members of which are arranged to ,make

a wiping contact.

The y/arious features of novelty which characterize my invention arepointed out with particularity in the claims annexed to and forming apart of this specification.

For a better understanding of lmy inven tion reference may be had to thefollowing description taken in connection with the accompanying drawing,in which Figure 1 is a view, partly in section, of a rotatable member ofa dynamo electric ma` chine embodying my invention; Fig. 2.is an endview of the member of the dynamo electric machine shown in Fig. 1, andFig. 3 is a diagram of connections.

Referring to'the drawing, 1 is a shaft o n which is mounted a rotatablemember of a dynamo electric machine, which' member comprises a core 2 inslots in the periphery of which is mounted a winding 3. Taps on thiswinding are brought out to Contact lmembers' 4, which may be connectedtogether by means of my centrifugal switch. This switch comprises amember 5 which surrounds the shaft 1, and is rotatable relative thereto,a spring 6 which opposes the movement of the member 5 around the shaft,and one or more pivoted, centrifugally operated members 7 mounted on themember 5 and tending to turn the same around the shaft. Preferably, oneend 8 of the spring 6 is fastened to the core 2 of the rotatable member,

of the dynamo electric machine and the other end 9 of this spring isfastened to the member 5. If desired, a series of projections 10 may beprovided on the member 5 so that the tension of the spring 6 maybeadjusted by moving the end 9 of the spring so as to envage differentprojections.

n order to rotate the member 5 rela- Specication of Letters Patent.

Patented @et 26, 1915. serial No'. 338,692.

tively to the shaft, a gear 1l is keyed to the shaft and the inner endsof the centrifugal members are provided with teeth 12, these teethmeshing with the teeth on the gear 11. rlhe centrifugal members arepivotally mounted on the studs 13, these studs in turn being mountedbetween a supporting plate 14 and the member 5. shown, the member 5 hasfastened thereto, a plate 15 having arms 16 which act as contact membersfor engaging the studs 4.

My invention may be used for controlling the circuit of any type ofdynamo yelectric machine, and in the diagram of Fig. 3, I have shown itapplied to a motor which starts as a repulsion motor and runs as aninduction motor. This motor has a field winding 17, which is connectedto alternating current mains 18, and an armature winding @connected to acommutator 19 and to the contact members 4. Bearing on the commutator1,79 are brushes 20 which are short-circuited on each other. Thecommutator is usually mounted at one end of the rotatable member of thedynamo electric machine and the contact members are mounted at the otherend. Since only a portion of the rotatable member of the machine isshown in F ig. 1, the commutator is not shown in this figure. When themachine is starting, the parts are as shown in the drawing, thecentrifugal members -7 being in their folded-in position, (see Fig. 2),and the contact arms 16 are out of engagement with the contact members4, the' spring 6 In the arrangement sition. The motor therefore, startsas a Simple repulsion motor and operates as such until it reaches aboutthree-fourths of its normal speed, whereupon the centrifugal members iiyoutwardly against the tension of the spring 6 and rotate relatively tothe shaft because of the engagement of the teeth 12 of the centrifugalmembers with the teeth on the gear wheel 11. The rotation of thecentrifuga-l members carries with them the member 5 until the contactarms 16 engage the contact members 4, whereupon the I points of thewinding 3 to which the hontact members 4 are connected are directlyshortcircuited and the motor operates as an induction motor. It will benoted that the ends of the Contact arms are slightly bent so that theywill easily ride upon the contact members 4. When the eld of the motoris disconnected from the line and the rotatable member comes to rest,the spring 6 rotates the member 5 and the centrifugal members to theposition shown in the drawmg.

Furthermore, although I have illustrated my invention in connection witha particular type of alternating current motor, I desire it to beunderstood that it is not limited in its use to such a motor, but may beused in numerous types of dynamo electric machines, and I aim in theappended claims-to cover all such modifications as Well as any otherswhich do not depart from thespirit and scope of my invention.

What I claim as neWand desire to secure by Letters Patent of the UnitedStates, is

l. In combination, a. shaft, a rotatable member of a dynamo electricmachine mounted on said shaft, and a centrifugally operated switchcontrolling a circuit of said machine comprising a member surroundingsaid shaft and rotatable relative thereto, a spring opposing themovement of said member around the shaft, a gear mounted on said shaft,and centrifugally operated members pivotally mounted on said membersurrounding the shaft, said centrifugally operated members having teethmeshing with the teeth of said gear and tending to turn said memberaround the shaft.

In combination, a shaft, 'a rotatable member of a dynamo electricmachine mounted on saidshaft, and a centrifugally operated switchcontrolling a circuit of said machine comprising a member surroundingsaid shaft and rotatable relative thereto, a spring opposing themovement of said lmember around the shaft, said spring having one endfastened to the rotatable member of the dynamo electric machine and the,other end fastened to the member surrounding the shaft, a gear mountedon said shaft, and centrifugally operated members pivoted on said membersurrounding theshaft,` said centrifugally operated members having teethmeshing `with the teeth on said,gear and tending to turn said memberaround the shaft.

In witness whereof, I have hereunto set vmy hand this 12th day of May1914.

JOHN B. WIARD.

Witnesses:

JOHN A. MoMANUs, Jr., ARTHUR M. STANLEY.

Copies of this 4patent may be obtained for ve cents each, by addressingthe Commissioner of Pat/ems,

Washington, D. C.

